References

Biogeosciences

1726-4189

Copernicus Publications

Göttingen, Germany

10.5194/bg-9-3357-2012

The European land and inland water CO2, CO, CH4 and N2O balance between 2001 and 2005

Luyssaert

¹ Abril

² Andres

³ Bastviken

⁴ Bellassen

¹ Bergamaschi

⁵ Bousquet

¹ Chevallier

¹ Ciais

¹ Corazza

⁵ Dechow

⁶ Erb

K.-H.

⁷ Etiope

⁸ Fortems-Cheiney

¹ Grassi

⁵ Hartmann

⁹ Jung

¹⁰ Lathière

¹ Lohila

¹¹ Mayorga

¹² Moosdorf

⁹ Njakou

D. S.

¹³ Otto

¹ Papale

¹⁴ Peters

¹⁵ Peylin

¹ Raymond

¹⁶ Rödenbeck

¹⁷ Saarnio

¹⁸ Schulze

E.-D.

¹⁰ Szopa

¹ Thompson

¹ Verkerk

P. J.

¹⁹ Vuichard

¹ Wang

²⁰ Wattenbach

²¹ Zaehle

¹⁷

CEA-CNRS-UVSQ, UMR8212 – Laboratoire des sciences du climat et de l'environnement (LSCE), Orme des Merisiers, 91191 Gif-sur-Yvette, France

Laboratoire EPOC, Environnements et Paléoenvironnements Océaniques et Continentaux, UMR5805, CNRS, Université de Bordeaux, Bordeaux, France

Oak Ridge National Laboratory, Environmental Sciences Division, Oak Ridge, TN 37831-6290, USA

Linköping University, The Department of Thematic Studies – Water and Environmental Studies, 586 62 Linköping, Sweden

European Commission, Joint Research Centre, Institute for Environment and Sustainability, Via E. Fermi 2749, 21027 Ispra (VA), Italy

Johann Heinrich von Thünen-Institut, Institute for Agricultural Climate Research, Bundesallee 50, 38116 Braunschweig, Germany

Alpen-Adria Universitaet Klagenfurt-Vienna-Graz, Institute of Social Ecology Vienna (SEC), Schottenfeldgasse 29, 1070 Vienna, Austria

Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 2, Via Vigna Murata 605, Italy

Institute for Biogeochemistry and Marine Chemistry, KlimaCampus, University of Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany

Max-Planck Institute for Biogeochemistry, Biogeochemical Processes, P.O. Box 100164, 07701 Jena, Germany

Finnish Meteorological Institute, Climate Change Research, P.O. Box 503, 00101 Helsinki, Finland

University of Washington, Applied Physics Laboratory, Box 355640, Seattle, WA 98105-6698, USA

University of Antwerp, Researchgroup Plant and Vegetation Ecology, Universiteitsplein 1, 2610 Wilrijk, Belgium

University of Tuscia, Department for innovation in biological, agro-food and forest systems (DIBAF), Via S. Camillo de Lellis, snc- 01100 Viterbo, Italy

Wageningen University, Meteorology and Air Quality, Droevendaalsesteenweg 4, 6700 PB, Wageningen, The Netherlands

Yale University, School of Forestry and Environmental Studies, 195 Prospect Street, New Haven, CT 06511, USA

Max Planck Institute for biogeochemistry, Biogeochemical Systems Department, P.O. Box 100164, 07701 Jena, Germany

University of Eastern Finland, Department of Biology and Finnish Environment Institute, the Joensuu Office, PL 111, 80101 Joensuu, Finland

European Forest Institute, Sustainability and Climate Change Programme, Torikatu 34, 80100 Joensuu, Finland

Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China

Helmholtz Centre Potsdam GFZ German Research Centre For Geosciences, Deutsches GeoForschungsZentrum GFZ, Telegrafenberg, 14473 Potsdam, Germany

24 08 2012

9 8 3357 3380

2012

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://bg.copernicus.org/articles/9/3357/2012/bg-9-3357-2012.html

The full text article is available as a PDF file from https://bg.copernicus.org/articles/9/3357/2012/bg-9-3357-2012.pdf

Globally, terrestrial ecosystems have absorbed about 30% of anthropogenic greenhouse gas emissions over the period 2000–2007 and inter-hemispheric gradients indicate that a significant fraction of terrestrial carbon sequestration must be north of the Equator. We present a compilation of the CO2, CO, CH4 and N2O balances of Europe following a dual constraint approach in which (1) a land-based balance derived mainly from ecosystem carbon inventories and (2) a land-based balance derived from flux measurements are compared to (3) the atmospheric data-based balance derived from inversions constrained by measurements of atmospheric GHG (greenhouse gas) concentrations. Good agreement between the GHG balances based on fluxes (1294 ± 545 Tg C in CO2-eq yr−1), inventories (1299 ± 200 Tg C in CO2-eq yr−1) and inversions (1210 ± 405 Tg C in CO2-eq yr−1) increases our confidence that the processes underlying the European GHG budget are well understood and reasonably sampled. However, the uncertainty remains large and largely lacks formal estimates. Given that European net land to atmosphere exchanges are determined by a few dominant fluxes, the uncertainty of these key components needs to be formally estimated before efforts could be made to reduce the overall uncertainty. The net land-to-atmosphere flux is a net source for CO2, CO, CH4 and N2O, because the anthropogenic emissions by far exceed the biogenic sink strength. The dual-constraint approach confirmed that the European biogenic sink removes as much as 205 ± 72 Tg C yr−1 from fossil fuel burning from the atmosphere. However, This C is being sequestered in both terrestrial and inland aquatic ecosystems. If the C-cost for ecosystem management is taken into account, the net uptake of ecosystems is estimated to decrease by 45% but still indicates substantial C-sequestration. However, when the balance is extended from CO2 towards the main GHGs, C-uptake by terrestrial and aquatic ecosystems is offset by emissions of non-CO2 GHGs. As such, the European ecosystems are unlikely to contribute to mitigating the effects of climate change.

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